Collecting Audio Phenomena.
One of the most common pieces of evidence collected today is electronic voice phenomena (EVP). A voice so low it's impossible or hard to hear with the human ear but is able to be captured on audio. These EVPs can be really good evidence. Again, there are a few things to remember.
We all know not to whisper during an EVP session.
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The person asking the questions always speaks in a loud clear voice. Unfortunately, others in the group frequently whisper to each other, even though they know they shouldn't. Those whispers frequently turn into an EVP a few days later.
Many times investigations are in old buildings where sound can easily travel through walls and even floors. People talking or walking on another floor or room can sound just like a ghost. Even outside street noise and voices can be caught on audio. We have heard EVPs that turned out to be a camera turning on, someone's stomach growling, or a furry critter scampering across the room. Always look for extraneous sources that could cause the noise.
Should someone cough or make a noise when moving, they need to clearly say what just happened. Even people with the best memory can't remember what was going on every second during an investigation. This becomes more apparent when the material collected may not be reviewed for several days or weeks.